Report of the Researches of M. Agassix. 307 



in the midst of the general uniformity ; thus, instead of a 

 bed of seven to ten feet, we find two of from three to four 

 feet in thickness. In this case, we must admit a long interval 

 between the snow-falls of the same winter. It is thus that, 

 during the winter of 1840-41, after the snows of autumn, the 

 environs of the Grimsel, and of the glacier of the Aar, enjoyed 

 throughout the whole months of December and January a mild 

 temperature and a serene sky. The temperature in the warmer 

 days must have been above zero even in the highest regions, 

 and this would have been sufficient to form a superficial crust ; 

 separating the snow which fell in autumn from that which fell 

 in spring. Hence we should not be astonished to find at some 

 future period a double stratum corresponding to this winter, 

 when, in consequence of the movement of the whole glacier, 

 these masses shall have been engaged in the common move- 

 ment. 



This explanation of the formation of the annual beds is so 

 natural, that I think it cannot be disputed by any one. Unfor- 

 tunately, the superposition of the beds is visible in the most 

 elevated positions only, where very few naturalists go to ex- 

 amine them. Lower down the nev6 succeeds, which is com- 

 pact, and here the crevasses are generally too few and shallow 

 to allow our observing the stratification ; and as to the glacier, 

 properly so called, it exhibits at its surface only very faint 

 traces of the phenomenon. It is only by ascending to an ele- 

 vated part of the highest ridges, where we command an exten- 

 sive view of the whole glacier, and by extending our prospect 

 from these upper regions, where the out-croppings of the beds 

 are very distinct, to the less elevated districts, that we perceive 

 these croppings extend from above downwards, but always less 

 and less distinct as we approach the extremity of the glacier. 

 By thus having the whole of the phenomenon at once under our 

 view, we are easily convinced that the strata exist throughout 

 the whole length of the glacier, however obscure they may ap- 

 pear at first sight. It is in this way much as it is in metamor- 

 phic rocks. At first view, no one would recognise beds in those 

 granitic walls which surround V Hospice du Gnmsel ; but if we 

 ascend one of the environing summits, we are soon persuaded, 

 while beholding the constant direction of the lines, that the 



